System and method for high resolution sensing of capacitance or other reactive impedance change in a large dynamic range
US7663377B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 3, 2007 |
| Grant date | Feb 16, 2010 |
| Priority date | — |
| Expiry date | Oct 2, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Systems and methods are provided for sensing or measuring capacitive or inductive reactance or changes in reactance in which the sensed reactance is coupled with a known resistance in a sensor circuit and a start signal is provided to the sensor circuit, and a programmable delay line is used to generate a programmable delay signal. The outputs of the programmable delay and the sensor circuits are compared to ascertain which transitions first, and the programmable delay value is adjusted in successive approximation fashion to identify a programmable delay that best represents the delay time of the sensor circuit from which the sensed reactance value can be determined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.